AES E-Library

Enhanced Sigma Delta Structures for Super Audio CD Applications

New Sigma Delta modulators (SDM's) topologies for use in Super Audio CD (SACD) applications are introduced, called Sigma Delta pre-correction (SDPC), which allow the generation of ultra-high quality DSD. Spurious peaks, which are known theoretically to exist in SDM's, are present at levels well below -165 dB, even if undithered. Already a slight amount of dither, will further reduce these signals to levels which are with standard numerical precision undetectable.